# Common Probability Distributions

** 1. Normal Distribution:**

\( {y = \frac{1}{{\sigma}{\sqrt {2 \pi}}}e^{\frac{-(x - \mu)^2}{2 \sigma}} }\)

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**Where:**

μ = Mean

σ = Standard Deviation

σ = Standard Deviation

π ≈ 3.141

e ≈ 2.718

e ≈ 2.718

**2. Binomial Distribution:**

\({P(x)} = ^{n}{C_x}.{p^x}.{q^{n-x}}\)

**Where:**

p = Probability of success

q = Probability of failure = 1−p

q = Probability of failure = 1−p

n = Number of trials

P(x) = Probability of x successes in n trials

P(x) = Probability of x successes in n trials

**3. Poisson Distribution:**

\({P(x)} = {e^{-m}}.\frac{m^x}{x!}\)

**Where:**

m = Probability of success

P(x) = Probability of x successes.

P(x) = Probability of x successes.